Band saw



Jan. 5, 1943.

F," M. BELL.

BAND SAW Filed May 20 1940 Patented Jan. 5, 1943 UNITED STATES PATENT OFFICE Application May 20, 1940, Serial No. 336,077

2 Claims.

This invention relates to improvements in band saws and more particularly to the type using a flexible endless saw band guided and supported on pulleys.

Objects of my invention include improvement in the means for adjusting and supporting the wheels or pulleys which carry the saw band, and in the arrangement and relationship of the pulleys, and in the construction of the frame of the machine.

A particular object is to provide such improvements singly or in combination in a form adapted for relatively deep throat machines, that is to say where a relatively large space is provided for rearward wprk clearance between the cutting run of the saw and the frame.

It is a further purpose generally to simplify and improve the construction and operation of band saws, and of the relationship of the parts of the machine, and still other objects will be appar-' ent from this specification.

The invention includes the construction and combination of parts herein illustrated, described and claimed, and such modifications thereof as may be equivalent to the structure claimed.

The same reference characters have been used for the same parts throughout this specification, and in the drawing.

Figure 1 is a front elevation of a band saw machine incorporating the invention.

Figure 2 is an enlarged rear elevation of the Fig. 1 left side portion of the machine.

Figure 3 ,is a sectional view showing a pulley support, taken at line 3-3 of Fig. 2.

Figure 4 is an enlarged partial section taken at line 4-4 of Fig. 3.

Figure 5 is an enlarged partial vertical section taken at line 5-5 in Fig. 1.

Figure 6 is a partial plan or top view taken at line 6-6 of Fig. 5.

The machine of the drawing includes a frame, generally denoted as 10, which has a base portion I (la and carries a work supporting table II, the table being preferably arranged in swivel guides such as Ila, in the usual manner.

A saw supporting and driving lower pulley I2 is fixed on a shaft l2a which is rotatably carried by the frame and may be driven from any suitable power source, such as a motor, not shown, as for example by a pulley |2b fixed on the shaft l2a. A rotatable upper pulley l3 and rotatable rear pulleys I4, I5, 16 are also carried by the frame l and, together with pulley l2, support an endless saw band, such as I1, for a front run or portion Tia to continuously move downwardly 55 through table I l there being a vertically adjusta ble saw guide device, generally denoted as l8, of any suitable well-known form, to support the saw against lateral thrust during sawing operations. Each of the pulleys may be provided witha facing of rubber, or similar. material as shown. for the pulley i5 at I5a.

The upper pulley i3 is supported from frame it! for vertical adjustment by the means of a vertically adjustable carrier 20, the carrier being movable on parallel guide members 2i, 2! fixed in a bracket 22 that is fixed on frame l6. Carrier 29 may have additional suitable guide surfaces directly engaging vertical slide surfaces on the bracket, as shown by the mutually engaged car rier and bracket surfaces of Fig. 6. The carrier 20 is adjusted upwardly by the means of an adjusting screw 24, for which suitable nut threads are provided in frame ill. The carrier is normally continuously urged in the other direction by gravity and by the pull of the saw band, and the carrier adjustment upwardly operates to provide suitable tension on the saw band.

Each of the pulleys I3, [4, l5, It is supported for both horizontal and lateral adjustment of the pulley center, and also for angular adjustment of the pulley axis. The mechanism for these adjustments is substantially the same for each of the pulleys and therefore will be explained in detail only for the pulley l5. In each instance the pulley is rotatably supported on a stud such as 26, preferably by anti-friction bearings such as 21, and is prevented from .axial movement relative to the stud. The studs such as 26 are fixed in the bore of tube or sleeve members such as 23 and, at the one end, the unit is prevented from axial movement by screws such as 29, each having points engaging a suitable configuration on the tube exterior, as shown. The frame provides an opening which is larger than the tube, and by suitable adjustment of the screws such as 29 the tube and pulley carried thereby may be adjusted for adjusting the pulley axis in any lateral direction, as stated.

At the other end the tubes such as 28 are each slotted to slidably engage over a guide bar or strip member, such as 30 which is suitably fixed with the frame. In this instance the guide strips 30 are extended and fixed in suitable slots provided in bosses fixed with the frame, the ends of the strips being bent to prevent endwise shifting,

bers such as 30 permit of adjustment of the ends effective working space or throat distance at the of the pulley carrier members such as 28, and left, Fig. 1, of the cutting run l'la of the saw the thrust direction of the screws such as 32 relband. ative to such adjustment is so arranged that the What is claimed is: axis of the associated saw supporting pulley may 5 1. In a band saw machine having a frame, a be adjusted for the saw band to track accurately work table supported therefrom, and a plurality on each pulley, without tending to run off the of spaced pulleys supported from said frame for pulley, while the adjusting screws such as 32 resupporting a saw band and guiding a cutting porceive the thrust set up by the pressure of the saw tion of the band for movement through an openband over the pulley. The drawing shows the ing in said table, the combination of mechanism approximate relative angles of the guide members for tilting the axis of one of said pulleys relative and screw thrust directions for each of the pulto another thereof including a non-rotatable leys l3, l4, 15, I6 which has been found to work member supported from said frame for tilta'ble well in practice with the pulley arrangement here adjustment movement, said tiltable member roshown. tatably supporting said tiltable pulley at the one It will be understood that, if desired, a correside of the tilting axis of the member, said tiltsponding or similar adjustment may be provided able member at an end at the other side of said for the pulley 12, for both or either of the lateral tilting a Providing Slot tend ng in the diand pivotal adjustments as described, rection of the tilting movement of said end about Where the frame of th ma i provides said axis, a guide member fixed with said frame relatively large throat space or work clearance, and slidably engaging d 013, and adjustin as here shown, difficulty is experienced in conmeans for movement of said slotted end alon structing a frame which provides'sufiicient latsaid guide member, said tiltable member bein eral and vertical resistance without exceeding depp d for bodily adjustment o S d t ltab e sirable weight of material and while still main-' p y in t r r t on in a h f mutual y taining construction convenience. It has been r s e p n sfound that a frame constructed with oppositely In a band Saw machine having frame, a formed similar channel-like portions such as in- Work table upp therefrom, a d a plura ity dicated at 35, 35, Fig. 5, separated along a verof sp p leys supported from said frame for tical transverse plane, such as is indicated by the supporting a saw band and guiding a cutting line 36, Figs. 3, 5, is particularly adapted to the p r n f the and f r m v t th h n purpose for this type of machine. It will be unopening in said table, the combination of mechderstood that the opposite channel portions are anism f tilting t s f e f s d p l y separately formed and bolted together, as by suitrelative to another thereof including an extended ably positioned bolts such as 31, 31, Fig. 1, and member rotatably supporting said tiltable p l y that each of the frame portions are providedand providing exterior abutment portions adjawith suitably disposed interior strengthening ribs, cent one end of the member and approximately etc. This provides a frame which is simple to in the same plane transverse to the direction of construct, pleasing in appearance, and of maxiextension of the member, a plurality of abutment mum strength with a given weight of material. screws carried by said frame to engage different The arrangement of the three rear pulleys 14, of said abutment portions respectively, said abutl5, [6, as here shown, has been found particument screws and abutment portions providing larly eflicient and useful in this type of machine, means supporting the member both for tilting especially where the various pulleys are adjustmovement relative to said plane and for lateral able, as has been described. Three pulleys, albodily adjustment of the member, the other end though relatively small in diameter, guide the of said member providing a slot extended latersaw band without short bend therein, such as ally in the direction of the tilting movement of would cause the saw band to crystallize and said other end, a guide member g g S d break. Thus, for example, a single pulley equivslot for guiding said tilting movement of said alent in this respect to the three pulleys arranged other end, and an adjusting device for movement as here shown would have a diameter approxiof said slotted end along said guide member. mately as indicated in the dot and dash line 40,

Fig. 1, such pulley diameter greatly reducing the FLOYD M. BELL. 

